| organs as studied by the professional botanist. An artificial key to the 
! 
| 
| greatest importance; otherwise the order of arrangement followed is 
| that of Bentham and Hooker’s Genera Plantarum. The nomenclature 

terms. The descriptions of the species do not pretend to be technical 
FOREST FLORA OF THE ROCKY MOUNTAIN REGION, 
By GrorGe bL. Supwortn, 
Forestry Division. 
The following chapter is intended to embody an account of all the 
strictly woody plants occurring in the Rocky Mountain region. These 
have been divided into arborescent and non-arborescent species. But 
the dividing line must necessarily be an arbitrary one, and undoubtedly 
many exceptions could be taken to the species thus termed arborescent, 
a large number being little more than shrubs as commonly found, yet 
the controlling feature has been rather the capabilities of each species 
under specially favorable conditions, such as may occur more or less in 
the region under consideration. 
Besides the range of each species within the Rocky Mountain region, 
the general distribution of those species not particularly confined to 
these limits has been placed in parentheses and given mostly in general 
(or even complete), the attempt here made being rather to avoid, as far 
as possible, the use of such botanical terms as will not be readily un- 
derstood by the laymen, and to note such characters as are most apt to 
be seen by the casual observer; hence the lack of attention to floral 
genera and species has been prepared on the same basis, and if is 
hoped will lend some aid to the laymen in studying the flora. A fuller 
description has been given only for the arborescent species. 
The conifers have been somewhat arbitrarily arranged and placed 
first, asin this region at least they are without doubt forestally of 
is that given by Dr. Gray in his Synoptical Flora of North America, 
supplemented by that adopted by Dr. George Englemann, Professors 
Sereno Watson, M. S. Bebb, and C. S. Sargent. As regards the com- 
mon names used, such confusion exists that it is difficult to determine 
which names are most used and most appropriate ; for in many sections 
| the same name is applied to different species. But it is highly desir- 
‘able for practical purposes that a uniformity in nomenclature should be 
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